Opera Files Antitrust Case Against Microsoft's Edge Tactics

Opera Files Antitrust Complaint in Brazil

Opera has officially filed a complaint with Brazil’s competition authority, accusing Microsoft of deploying a range of manipulative design tactics to steer Windows users toward its Edge browser. This escalation marks Opera’s response to years of alleged anti-competitive actions that undermine consumer choice.

Accusations of Manipulative Design Tactics

According to Opera’s complaint, Microsoft routinely ignores users’ default browser settings across multiple scenarios, effectively locking alternative browsers out of key workflows. From opening PDFs in Edge after download to hijacking links in Outlook, Teams, Windows Search, and Widgets, Opera says Microsoft leaves little room for choice.

• Default settings overridden when opening PDFs, links, and documents
• Obtrusive banners on Edge discouraging users from downloading alternatives
• Hidden restrictions on S mode devices tied to OEM rebates for Windows licenses

Desired Remedies

Opera is seeking several key changes to restore balance and fair play in the browser market:

• Allow PC manufacturers to preload and promote alternative default browsers
• Prohibit Microsoft from blocking or frustrating consumer downloads of other browsers
• End all dark patterns and discouraging messages that push users toward Edge

Broader Context and Impact

Brazil is a critical market for Opera, where it ranks third in browser usage. By filing here, Opera not only targets global Windows practices but also positions Brazil as a leader in combating anti-competitive tech conduct.

This move follows Opera’s earlier challenges under Europe’s Digital Markets Act and decades of legal battles dating back to its 2007 complaint, which led to the browser choice screen in Windows.

What’s Next for Browser Competition

If Brazil’s antitrust authority rules in Opera’s favor, it could force Microsoft to dismantle its high-barrier tactics globally. The outcome may reshape how operating systems handle defaults and level the playing field for all browsers.

For enterprises and developers, these changes could open new opportunities for integrating alternative browsers into corporate environments without fear of system-level overrides. Organizations monitoring user experience compliance will find fresh momentum in advocacy and regulatory standards.